HIIT is a cardio session arranged as short bursts of very hard work. The whole point of high-intensity training is to kick up the intensity of your cardio. In order to qualify as true HIIT, you’ll need to push yourself to the max during every set. That’s why they’re short—anywhere from 20 to 90 seconds, typically. It’s the opposite of going for a long run where you ration your energy in order to sustain the activity for longer.
High-intensity interval training (HIIT), also called high-intensity intermittent exercise (HIIE) or sprint interval training (SIT), is a form of interval training, a cardiovascular exercise strategy alternating short periods of intense anaerobic exercise with less intense recovery periods, until too exhausted to continue. Though there is no universal HIIT session duration, these intense workouts typically last under 30 minutes, with times varying based on a participant’s current fitness level. The duration of HIIT also depends on the intensity of the session.
HIIT workouts provide improved athletic capacity and condition as well as improved glucose metabolism. Research has shown that HIIT regimens produced significant reductions in the fat mass of the whole-body.